1. Field of the Invention
The present invention relates to a filler tube assembly for vehicles which forms a passage for injecting a liquid fuel from a fuel injector to a fuel tank of a vehicle.
2. Description of the Prior Art
Vehicles generally are provided with fuel tanks for storing a fuel required for drive of the vehicle and supplying the fuel to an engine to drive the engine. A filler tube is installed on one side of the fuel tank, and serves as a passage for receiving a liquid fuel from a fuel injector (a filling gun) and hermetically transferring it to the fuel tank.
More specifically, the filler tube is a vehicular component for coupling the fuel injector to the fuel tank. Since the fuel for running vehicle engines is very volatile and thus explosive, the filler tube is a major safety component which should be designed and manufactured to prevent leakage of the fuel at a vehicle accident or overturn or due to long-term use.
Filler tubes currently manufactured at home and abroad at present are generally made of plastic or carbon steel. This material has limited the weight reduction of the vehicle, and contains hazardous substances in an environment. In addition, it leads to increase a manufacturing cost of the vehicle, because of increased plating material for corrosion resistance.
More specifically, a plastic filler tube has 3-Dimensional shape by extrusion blow molding, and is rigidly manufactured and applied to the vehicle. Since a large quantity of hydrocarbon gas penetrates the plastic, the filler tube should be subjected to fluorine coating process (fluorinate) which is expensive and harmful to environment and human body, so as to enhance the sealing performance against transmission of the hydrocarbon gas. As times of fuel injection are increased, the coating is worn and damaged by continuous flow of the fuel, so that the sealing performance against transmission of the hydrocarbon gas is significantly deteriorated.
In addition, since the carbon steel tube is relatively heavy, it runs against the tendency to make a body for a vehicle light, and the carbon steel tube contains substances harmful to an environment (for example, chlorine compound).